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Paula Fagundes de Gouvêa, Aline Vianna Bernardi, Luis Eduardo Gerolamo, Emerson de Souza Santos, Diego Mauricio Riaño-Pachón, Sergio Akira Uyemura, Taisa Magnani Dinamarco
BACKGROUND: Sugarcane bagasse has been proposed as a lignocellulosic residue for second-generation ethanol (2G) produced by breaking down biomass into fermentable sugars. The enzymatic cocktails for biomass degradation are mostly produced by fungi, but low cost and high efficiency can consolidate 2G technologies. A. fumigatus plays an important role in plant biomass degradation capabilities and recycling. To gain more insight into the divergence in gene expression during steam-exploded bagasse (SEB) breakdown, this study profiled the transcriptome of A...
April 3, 2018: BMC Genomics
Jaire Alves Ferreira Filho, Maria Augusta Crivelente Horta, Lilian Luzia Beloti, Clelton Aparecido Dos Santos, Anete Pereira de Souza
BACKGROUND: Trichoderma harzianum is used in biotechnology applications due to its ability to produce powerful enzymes for the conversion of lignocellulosic substrates into soluble sugars. Active enzymes involved in carbohydrate metabolism are defined as carbohydrate-active enzymes (CAZymes), and the most abundant family in the CAZy database is the glycoside hydrolases. The enzymes of this family play a fundamental role in the decomposition of plant biomass. RESULTS: In this study, the CAZymes of T...
October 12, 2017: BMC Genomics
Henrik Marcus Geertz-Hansen, Lars Kiemer, Morten Nielsen, Kiril Stanchev, Nikolaj Blom, Søren Brunak, Thomas Nordahl Petersen
Thermostable enzymes for conversion of lignocellulosic biomass into biofuels have significant advantages over enzymes with more moderate themostability due to the challenging application conditions. Experimental discovery of thermostable enzymes is highly cost intensive, and the development of in-silico methods guiding the discovery process would be of high value. To develop such an in-silico method and provide the data foundation of it, we determined the melting temperatures of 602 fungal glycoside hydrolases from the families GH5, 6, 7, 10, 11, 43, and AA9 (formerly GH61)...
November 2017: Proteins
Van V Vu, Michael A Marletta
Polysaccharide degradation by hydrolytic enzymes glycoside hydrolases (GHs) is well known. More recently, polysaccharide monooxygenases (PMOs, also known as lytic PMOs or LPMOs) were found to oxidatively degrade various polysaccharides via a copper-dependent hydroxylation. PMOs were previously thought to be either GHs or carbohydrate binding modules (CBMs), and have been re-classified in carbohydrate active enzymes (CAZY) database as auxiliary activity (AA) families. These enzymes include cellulose-active fungal PMOs (AA9, formerly GH61), chitin- and cellulose-active bacterial PMOs (AA10, formerly CBM33), and chitin-active fungal PMOs (AA11)...
July 2016: Cellular and Molecular Life Sciences: CMLS
Thamy Lívia Ribeiro Corrêa, Leandro Vieira dos Santos, Gonçalo Amarante Guimarães Pereira
The lignocellulosic biomass, comprised mainly of cellulose, hemicellulose, and lignin, is a strong competitor for petroleum to obtain fuels and other products because of its renewable nature, low cost, and non-competitiveness with food production when obtained from agricultural waste. Due to its recalcitrance, lignocellulosic material requires an arsenal of enzymes for its deconstruction and the consequent release of fermentable sugars. In this context, enzymes currently classified as auxiliary activity 9 (AA9/formerly GH61) and 10 (AA10/formerly CBM 33) or lytic polysaccharide monooxygenases (LPMO) have emerged as cellulase boosting enzymes...
January 2016: Applied Microbiology and Biotechnology
Magali Tanghe, Barbara Danneels, Andrea Camattari, Anton Glieder, Isabel Vandenberghe, Bart Devreese, Ingeborg Stals, Tom Desmet
The auxiliary activity family 9 (AA9, formerly GH61) harbors a recently discovered group of oxidative enzymes that boost cellulose degradation. Indeed, these lytic polysaccharide monooxygenases (LPMOs) are able to disrupt the crystalline structure of cellulose, thereby facilitating the work of hydrolytic enzymes involved in biomass degradation. Since these enzymes require an N-terminal histidine residue for activity, their recombinant production as secreted protein is not straightforward. We here report the expression optimization of Trichoderma reesei Cel61A (TrCel61A) in the host Pichia pastoris...
December 2015: Molecular Biotechnology
Sera Jung, Younho Song, Ho Myeong Kim, Hyeun-Jong Bae
Lignocellulose is a renewable resource that is extremely abundant, and the complete enzymatic hydrolysis of lignocellulose requires a cocktail containing a variety of enzyme groups that act synergistically. The hydrolysis efficiency can be improved by introducing glycoside hydrolase 61 (GH61), a new enzyme that belongs to the auxiliary activity family 9 (AA9). GH61was isolated from Gloeophyllum trabeum and cleaves the glycosidic bonds on the cellulose surface via oxidation of various carbons. In this study, we investigated the properties of GH61...
September 2015: Enzyme and Microbial Technology
Jinguang Hu, Richard Chandra, Valdeir Arantes, Keith Gourlay, J Susan van Dyk, Jack N Saddler
The pretreatment process used and the nature of the biomass feedstock will influence the role that accessory enzymes can play in synergistically interacting with cellulases to effectively deconstruct the substrate. The work reported here assessed the possible boosting effects of the xylanase and lytic polysaccharide monooxygenase (AA9, formerly known as GH61) on the hydrolytic potential of cellulase enzyme mixtures during hydrolysis of steam pretreated poplar and corn stover at high (10-20% w/v) substrate concentrations...
June 2015: Bioresource Technology
Ingo Morgenstern, Justin Powlowski, Adrian Tsang
Our understanding of fungal cellulose degradation has shifted dramatically in the past few years with the characterization of a new class of secreted enzymes, the lytic polysaccharide monooxygenases (LPMO). After a period of intense research covering structural, biochemical, theoretical and evolutionary aspects, we have a picture of them as wedge-like copper-dependent metalloenzymes that on reduction generate a radical copper-oxyl species, which cleaves mainly crystalline cellulose. The main biological function lies in the synergism of fungal LPMOs with canonical hydrolytic cellulases in achieving efficient cellulose degradation...
November 2014: Briefings in Functional Genomics
Van V Vu, William T Beeson, Elise A Span, Erik R Farquhar, Michael A Marletta
The recently discovered fungal and bacterial polysaccharide monooxygenases (PMOs) are capable of oxidatively cleaving chitin, cellulose, and hemicelluloses that contain β(1→4) linkages between glucose or substituted glucose units. They are also known collectively as lytic PMOs, or LPMOs, and individually as AA9 (formerly GH61), AA10 (formerly CBM33), and AA11 enzymes. PMOs share several conserved features, including a monocopper center coordinated by a bidentate N-terminal histidine residue and another histidine ligand...
September 23, 2014: Proceedings of the National Academy of Sciences of the United States of America
In Jung Kim, Hee Jin Lee, In-Geol Choi, Kyoung Heon Kim
Reducing the enzyme loadings for enzymatic saccharification of lignocellulose is required for economically feasible production of biofuels and biochemicals. One strategy is addition of small amounts of synergistic proteins to cellulase mixtures. Synergistic proteins increase the activity of cellulase without causing significant hydrolysis of cellulose. Synergistic proteins exert their activity by inducing structural modifications in cellulose. Recently, synergistic proteins from various biological sources, including bacteria, fungi, and plants, were identified based on genomic data, and their synergistic activities were investigated...
October 2014: Applied Microbiology and Biotechnology
Ausra Peciulyte, George E Anasontzis, Katarina Karlström, Per Tomas Larsson, Lisbeth Olsson
The industrial production of cellulolytic enzymes is dominated by the filamentous fungus Trichoderma reesei (anamorph of Hypocrea jecorina). In order to develop optimal enzymatic cocktail, it is of importance to understand the natural regulation of the enzyme profile as response to the growth substrate. The influence of the complexity of cellulose on enzyme production by the microorganisms is not understood. In the present study we attempted to understand how different physical and structural properties of cellulose-rich substrates affected the levels and profiles of extracellular enzymes produced by T...
November 2014: Fungal Genetics and Biology: FG & B
Laetitia Poidevin, Jean-Guy Berrin, Chloé Bennati-Granier, Anthony Levasseur, Isabelle Herpoël-Gimbert, Didier Chevret, Pedro M Coutinho, Bernard Henrissat, Senta Heiss-Blanquet, Eric Record
The genome of the coprophilous fungus Podospora anserina harbors a large and highly diverse set of putative lignocellulose-acting enzymes. In this study, we investigated the enzymatic diversity of a broad range of P. anserina secretomes induced by various carbon sources (dextrin, glucose, xylose, arabinose, lactose, cellobiose, saccharose, Avicel, Solka-floc, birchwood xylan, wheat straw, maize bran, and sugar beet pulp (SBP)). Compared with the Trichoderma reesei enzymatic cocktail, P. anserina secretomes displayed similar cellulase, xylanase, and pectinase activities and greater arabinofuranosidase, arabinanase, and galactanase activities...
September 2014: Applied Microbiology and Biotechnology
Leila Lo Leggio, Ditte Welner, Leonardo De Maria
Recent years have witnessed a spurt of activities in the elucidation of the molecular function of a class of proteins with great potential in biomass degradation. GH61 proteins are of fungal origin and were originally classified in family 61 of the glycoside hydrolases. From the beginning they were strongly suspected to be involved in cellulose degradation because of their expression profiles, despite very low detectable endoglucanase activities. A major breakthrough came from structure determination of the first members, establishing the presence of a divalent metal binding site and a similarity to bacterial proteins involved in chitin degradation...
2012: Computational and Structural Biotechnology Journal
Zarah Forsberg, Asmund Kjendseth Røhr, Sophanit Mekasha, K Kristoffer Andersson, Vincent G H Eijsink, Gustav Vaaje-Kolstad, Morten Sørlie
Lytic polysaccharide monooxygenases (LPMOs), found in family 9 (previously GH61), family 10 (previously CBM33), and the newly discovered family 11 of auxiliary activities (AA) in the carbohydrate-active enzyme classification system, are copper-dependent enzymes that oxidize sp(3)-carbons in recalcitrant polysaccharides such as chitin and cellulose in the presence of an external electron donor. In this study, we describe the activity of two AA10-type LPMOs whose activities have not been described before and we compare in total four different AA10-type LPMOs with the aim of finding possible correlations between their substrate specificities, sequences, and EPR signals...
March 18, 2014: Biochemistry
Morten N Grell, Tore Linde, Sanne Nygaard, Kåre L Nielsen, Jacobus J Boomsma, Lene Lange
BACKGROUND: The fungus gardens of leaf-cutting ants are natural biomass conversion systems that turn fresh plant forage into fungal biomass to feed the farming ants. However, the decomposition potential of the symbiont Leucocoprinus gongylophorus for processing polysaccharides has remained controversial. We therefore used quantifiable DeepSAGE technology to obtain mRNA expression patterns of genes coding for secreted enzymes from top, middle, and bottom sections of a laboratory fungus-garden of Acromyrmex echinatior leaf-cutting ants...
2013: BMC Genomics
Glyn R Hemsworth, Bernard Henrissat, Gideon J Davies, Paul H Walton
Lytic polysaccharide monooxygenases (LPMOs) are a recently discovered class of enzymes capable of oxidizing recalcitrant polysaccharides. They are attracting considerable attention owing to their potential use in biomass conversion, notably in the production of biofuels. Previous studies have identified two discrete sequence-based families of these enzymes termed AA9 (formerly GH61) and AA10 (formerly CBM33). Here, we report the discovery of a third family of LPMOs. Using a chitin-degrading exemplar from Aspergillus oryzae, we show that the three-dimensional structure of the enzyme shares some features of the previous two classes of LPMOs, including a copper active center featuring the 'histidine brace' active site, but is distinct in terms of its active site details and its EPR spectroscopy...
February 2014: Nature Chemical Biology
Van V Vu, William T Beeson, Christopher M Phillips, Jamie H D Cate, Michael A Marletta
The ubiquitous fungal polysaccharide monooxygenases (PMOs) (also known as GH61 proteins, LPMOs, and AA9 proteins) are structurally related but have significant variation in sequence. A heterologous expression method in Neurospora crassa was developed as a step toward connecting regioselectivity of the chemistry to PMO phylogeny. Activity assays, as well as sequence and phylogenetic analyses, showed that the majority of fungal PMOs fall into three major groups with distinctive active site surface features. PMO1s and PMO2s hydroxylate glycosidic positions C1 and C4, respectively...
January 15, 2014: Journal of the American Chemical Society
Chiaki Hori, Jill Gaskell, Kiyohiko Igarashi, Masahiro Samejima, David Hibbett, Bernard Henrissat, Dan Cullen
To degrade the polysaccharides, wood-decay fungi secrete a variety of glycoside hydrolases (GHs) and carbohydrate esterases (CEs) classified into various sequence-based families of carbohydrate-active enzymes (CAZys) and their appended carbohydrate-binding modules (CBM). Oxidative enzymes, such as cellobiose dehydrogenase (CDH) and lytic polysaccharide monooxygenase (LPMO, formerly GH61), also have been implicated in cellulose degradation. To examine polysaccharide-degrading potential between white- and brown-rot fungi, we performed genomewide analysis of CAZys and these oxidative enzymes in 11 Polyporales, including recently sequenced monokaryotic strains of Bjerkandera adusta, Ganoderma sp...
November 2013: Mycologia
Jinguang Hu, Valdeir Arantes, Amadeus Pribowo, Jack N Saddler
BACKGROUND: Currently, the amount of protein/enzyme required to achieve effective cellulose hydrolysis is still too high. One way to reduce the amount of protein/enzyme required is to formulate a more efficient enzyme cocktail by adding so-called accessory enzymes such as xylanase, lytic polysaccharide monooxygenase (AA9, formerly known as GH61), etc., to the cellulase mixture. Previous work has shown the strong synergism that can occur between cellulase and xylanase mixtures during the hydrolysis of steam pretreated corn stover, requiring lower protein loading to achieve effective hydrolysis...
2013: Biotechnology for Biofuels
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